Top Features . BlueTrack Technologyupto 8-month battery lifeComfortable in either hand . A mobile mouse for perfect for comfort and style on the go You\'ll appreciate how this wireless mobile mouse comfortably fits your hand and your mobile lifestyle. Use it just about anywhere even on a rough park bench or your living room carpet relying on Microsoft BlueTrack Technology.When it’s time to pack up and go you’ll hardly notice the tiny transceiver. Keep it plugged into the USB port or stow it in the bottom of the mouse for travel. Keep using your mouse for up to eight months with a single battery and rely on the power indicator to tell you when it’s time to replace it..